Ice Core Moraine Sign - Why the blue ice?

The sign states: "Notice the brilliant blue ice peaking out from under a thin layer of rock and mud? This is an ice core moraine. These moraines are created when till or other rock debris covers a portion of a glacier, insulating the ice from summer heat, rain and wind. Because the ice below is protected, it melts at a slower rate than exposed ice. Glacial ice is extremely dense and absorbs long wavelength colours, such as red, while reflecting shorter wavelength blues back to the onlooker - the finest of nature's palette!"